ISO 81060-2:2018/Amd 2:2024
Non-invasive sphygmomanometers

Standard No.

ISO 81060-2:2018/Amd 2:2024

Release Date

2024

Published By

International Organization for Standardization (ISO)  IX  /  ISO

Latest

ISO 81060-2:2018/Amd 2:2024

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Introduction

Core content of the standard revision

This revision mainly targets three key areas in the clinical evaluation of non-invasive sphygmomanometers:

• Scope of cuff system evaluation: Clarify that cuffs of different materials/structures need to be tested independently
• Subject allocation principle: Add a new uniqueness requirement (each subject only participates in one evaluation)
• Limb size distribution: Refine the subject allocation formula for different cuff size ranges

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New rules for cuff group testing

Cuff size range	Subject allocation requirements	Minimum sample size formula
≤12cm	40% in the upper half, 40% in the lower half	Ncuff=2×(rcuff/rtotal)×Ntotal
12-16cm	Each quartile ≥20%	Ncuff=(2/12)×(rcuff/rtotal)×Ntotal×rcuff
＞16cm	Each quartile ≥20%, highest/lowest octave ≥10% respectively	Same as 12-16cm formula

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Clinical study report requirements

New visual analysis tools

The amendment requires the inclusion of two types of analysis charts:

1. Arm circumference-error distribution chart: The X-axis is the actual arm circumference, and the Y-axis shows the difference between the test equipment and the reference value. The applicable range of each cuff must be marked with a vertical line
2. Bland-Altman chart: The X-axis is the average of the test value and the reference value, and the Y-axis shows the difference between the two. The systolic/diastolic blood pressure data must be distinguished

Example: When a manufacturer was evaluating the double-tube reusable cuff, it was found that the diastolic blood pressure measurement error in the 16-18cm arm circumference segment exceeded the ±5mmHg standard. The problem was solved by improving the balloon pressure distribution.

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Implementation recommendations

Phase-based validation strategy

• Pre-test phase: First, conduct 12-person validation on the smallest cuff size (e.g., 8-10 cm) to confirm the applicability of formula (18)
• Main trial design: When the total evaluation range rtotal＞35 cm, independent clinical research should be conducted in groups
• Data collection: 5-10 valid data measurements are collected for each patient, and the original measurement values are recorded using an electronic CRF

Key points for compliance check

Regulators will focus on checking:

• No duplication of subject IDs in different cuff groups
• The proportion of subjects in each size segment meets the requirements of the new formula
• The report contains a complete Bland-Altman analysis

ISO 81060-2:2018/Amd 2:2024 history

• 2024 ISO 81060-2:2018/Amd 2:2024 Non-invasive sphygmomanometers
• 2020 ISO 81060-2:2018/Amd 1:2020 Non-invasive sphygmomanometers — Part 2: Clinical investigation of intermittent automated measurement type — Amendment 1
• 2018 ISO 81060-2:2018 Non-invasive sphygmomanometers - Part 2: Clinical investigation of intermittent automated measurement type
• 2013 ISO 81060-2:2013 Non-invasive sphgmomanometers-Part 2:Clinical investigation of automated measurement type
• 2011 ISO 81060-2:2009/Cor 1:2011 Non-invasive sphygmomanometers - Part 2: Clinical validation of automated measurement type; Technical Corrigendum 1
• 2009 ISO 81060-2:2009 Non-invasive sphygmomanometers - Part 2: Clinical validation of automated measurement type

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